Field of the Invention
The present invention relates to a new and useful apparatus for prestressing concrete structures or the like, such as reservoirs, nuclear reactor housings, pipe and pressure vessels in general, although it will be appreciated that the invention in its broader aspects is useful for other purposes, such as, for example, laying cables under controlled tension.
It is a commonly used practice to wrap or bind concrete tanks with a continuous spiral of wire which maintains the wall of the tank under prestressed compression at all times regardless of variations in internal hydraulic pressure as the tank is filled or emptied.